Fire extinguisher



Feb. 3, 1959 L. E. DOAK FIRE EXTINGUISHER Fild May 20, 1957 l I i g I ii INVENTOR.

FIRE EXTINGUISHER Lyle E. Doak, Circle Pines, Minn. Application May20,1957, Serial No. 660,109

3 Claims. ((11. 169--26) This invention relates to fire extinguishersand more particularly relates to fire extinguishers containing aquantity of non-conducting fire extinguishing liquid under pressure tobe released upon the occurrence of a fire.

An object of my invention is to provide a new and improved fireextinguisher of simple and inexpensive construction and operation.

Another object of my invention is the provision of a novel fireextinguisher of the cartridge type, substantially filled with afire-extinguishing liquid under pressure and which is provided with anovel valve mechanism facilitating ready and easy charging of thecartridge and expelling of the liquid for extinguishing a fire.

A further object of my invention is the provision in a cartridge-typefire extinguisher of a frangible, fluiddischarging stem which isnormally closed and which is easily broken by mechanism operating inresponse to the occurrence of a fire in the immediate area, and whichalso has the function of operating as a valve facilitating ready andeasy charging of the cartridge.

These and other objects and advantages of my invention will more fullyappear from the following descrip tion made in connection with theaccompany drawings wherein like reference characters refer to the sameor similar parts throughout the several views and in which: Fig. 1 is anelevation'view of the extinguisher applied to a Christmas tree andshowing the manner in which the fire extinguishing fluid is dischargedtherefrom so as to envelop the entire tree; Fig. 2 is a section viewtaken on a vertical plane longitudinally through the extinguisher;

Fig. 3 is an enlarged detail section view of the valve mechanism andfrangible stem in ruptured condition and wherein the fire extinguishingfluid is being discharged; and

Fig. 4 is a detail section of the fluid diffuser and taken on asubstantially horizontal plane at 4-4 in Fig. 2.

One form of the present invention is shown in the drawings and isdescribed herein. The cartridge-type fire extinguisher includes a closedcontainer indicated in general by the numeral and being constructed oftwo shell halves 10a and 10b which are interconnected in sealed relationto each other by a crimped connection 10c. The lower shell 1% has adownwardly extending, cup-shaped receptacle 11 formed integrally thereofand provided with an aperture 12 in the bottom wall thereof. Theopening-defining portions 13 disposed peripherally around the aperture12 define a valve-sealing portion, and an annular gasket 14 is appliedonto the valve-seating portion 13.

A hollow frangible stem 15 has an open upper end 15a which projectsthrough the aperture 12 and into the interior of the container, slightlyabove the valveseating portion 13. The stem 15 has a transverselyoutwardly projecting annular flange 16 at the upper end thereof andformed integrally thereof and defining a 2 valve element seatableagainst the valve-seating portion 13 and gasket 14.

Means are provided for urging and holding the stem 15 downwardly so asto urge and hold the flange or valve element 16 against the seatingportion of the container. In the form shown, a rigid bar 17 extendsacross the inner end of the receptacle 11 and is aflixed at its oppositeends by any suitable means such as spot welds to diametrically oppositeportions of the lower container shell 10b. The central portion of thebar 17 is disposed directly above the stem 15. A spring 18 is disposedbetween the bar 17 and the stem 15, the lower end of the spring 18surrounding the upper end 15a of the stem and bearing against the flange16.

Stem 15, which is constructed of a frangible material such as glass orplastic, has a diminished lower end portion 18 which is closed, andwhich is provided with an annular stem-weakening groove 20 disposedslightly above the bottom end. Discharge of the fire-extinguishingliquid from the cartridge 10 is accomplished by breaking or rupturingthe stem 15 at the weakened portion thereof.

Means are provided for rupturing the stem 15 adjacent the lower endthereof and in response to the presence of a fire in proximity with theextinguisher. In the form shown, such means include an impact element orhammer 21 which, in the form shown, comprises an elongated bar having anelongated slot 22 therethrough and extending lengthwise thereof forreceiving thelower end 19 of the stem 15 therethrough. The impactelement 21 is supported from a plurality of depending frame elements 23which are interconnected at their lower ends by means of a diffuser 24hereinafter more fully described, and are interconnected at their upperends by a ring which encircles the receptacle 11. The peripheral wall11a of the receptacle has a number of recesses 11b and theinterconnecting ring on frame elements 23 has corresponding detents 23atherein which fit into the recesses 11b for holding the frame elementsin position. The impact element has a fusible link 25 at the inner endthereof which may be formed integrally of the element 21 and which is inturn connected with a mounting element 26 which is fixed by any suitablemeans, such as a tab 28 projecting through a suitable aperture in theframe element 23 and bent fiat against the outer side of the frameelement.

Means are provided for actuating the impact element 21, causing the sameto engage and break the stem 15 when the fusible link 25 ruptures. Inthe form shown, a tension spring 28 is connected to the outer end of theimpact element 21 and is connected to the outer side of the container 16in spaced relation with the receptacle .11. A spring-guiding bar 29extends transversely of the impact element 21 above the spring 23 and isaffixed at its opposite ends to adjacent frame elements 23 for guidingthe spring and causing the impact element 21 to be urged in a directiontransversely of the stem 15.

The diffuser 24, which may be formed integrally of the frame elements 23has a central convex top surface portion 30 disposed below the lower endof the stem 15, and the diffuser 24 also has an annular concave topsurface portion 31 surrounding the central portion and disposedtransversely outwardly from the end of the stem 15.

Of course the cartridge 10 may be provided with any suitable means forsecuring the extinguisher onto a Christmas tree and the like and in theform shown, a hanger or hook 32 is afiixed to the top of the container10 as by spot welding.

One of the important features of the present invention is theconstruction thereof which facilitates ready and easy charging of thecontainer with compressed air or other gas and fluid after the partshave been assembled in manufacture. The material with which thecartridge is to be charged is supplied under pressure around the stemand receptacle 11, and this application of material under pressure maybe accomplished by any suitable means such as a rubber supply nozzlewhich may be applied around the periphery of receptacle 11 before theframe elements 23 and diffuser 24 are secured thereon.

By application of pressure onto the outside of stem 15,

the stem will move inwardly, lifting the flange 1.6 off the gasket 14and causing material to be injected into the interior of the container.The aperture 12 in the bottom of the receptacle 11 is slightly largerthan the external diameter of the stern and the material passes easilythereby. It is preferred that compressed air at approximately five toseven p. s. i. be injected into the container along with a quantity ofthe non-conducting fire extinguisher liquid.

In operation, the fire extinguisher may be hung adjacent the top of aChristmas treeas shown in Fig. 1 or in any other hazardous locationwherein a fire would spread and go out of control rapidly, if notimmediately extinguished. If a fire were to occur in the Christmas tree,the temperature in the area of the fusible link 25 would immediatelycause the link to fuse. In this form of the invention the fusible linkhas a rated rupture temperature of approximately 140 degrees F. When thelink 25 ruptures, the spring 28 causes the impact element to strike andrupture the lower end of the stem 15. The stem 15 will break at theweakened groove 20 and compressed air at 33 in the container and abovethe liquid will cause the liquid to be expelled through the rupturedstem 15. The expelling liquid will engage the central convex portion ofthe diffuser and will flow transversely outwardly in multidirections andbe diffused upwardly by the convex peripheral portion 21, whereupon thefire extinguishing fluid, which will substantially vaporize and envelopthe entire Christmas tree T in the manner shown by the dotted lines F inFig. 1.

It will be seen that I have provided a new and improved extinguisherwhich has an improved frangible stem for ejecting the fire-extinguishingfluid in response to presence of heat and which is arranged to provide asimple valve mechanism to facilitate ready and easy charging of theextinguisher with fire-extinguishing liquid and compressed air.

It will, of course, be understood that various changes may be made inthe form, detail, arrangement and proportion of the parts withoutdeparting from the scope of my invention which consists of the matterdescribed herein and set forth in the appended claims.

What I claim is:

1. A cartridge-type fire extinguisher, comprising a closed containeradapted to contain a quantity of fire-extinguishing liquid under gaspressure, said container having an aperture in the bottom thereofdefining valve-seating portions therearound, a hollow frangible stemhaving a closed lower end disposed outwardly of the container andadapted to be ruptured, said stem also having an open upper endprojecting through the aperture in the container and an enlargedexternal periphery on the upper end thereof engaging and seating againstsaid seating portion at the inner side of the aperture in the container,and spring means urging the Stern outwardly, the stern being smaller inexternal configuration than the configuration of the aperture in thecontainer, whereby to facilitate charging of the container with fluidand gas by a plication of the gas and fluid under pressure to theexternal side of the container and stem.

2. A cartridge-type fire extinguisher comprising a closed containeradapted to contain a quantity of fire extinguishing liquid and gas underpressure and having an aperture in the bottom thereof, the containerdefining a valve-seating portion peripherally around the aperture and onthe inner side of the container, a hollow stem having an externallyflanged open upper end projecting through the aperture and also having afrangible closed outer end projecting outwardly from the aperture in thecontainer, the flange defining a valve element and hearing against thevalve-seating portion around the aperture in sealing relation, acompression spring bearing against the flanged upper end 'of the stemand urging the same toward the seating portion, anchoring means in thecontainer restricting upward movement of the spring, and said aperturebeing larger than the external periphery of the stem whereby to permitinflow of liquid applied under pressure to the outer side of thecontainer around the stem.

3. A cartridge-type fire extinguisher comprising a container adapted tocontain a quantity of fire extinguishing fluid and gas under pressure,and having an opening in the bottom thereof, a hollow stem in theopening and immovable in an outward direction, said stem having an openinner end communicating with the interior of the container and having adiminished and weakened frangible lower end projecting outwardly fromthe container, an elongated and generally horizontal impact elementhaving an elongated slot therein receiving the diminished lower end ofthe stem therethrough, a fusible link connected to one end of the impactelement, anchoring means 1 connecting the fusible link with thecontainer for holding References Cited in the file of this patent UNITEDSTATES PATENTS 1,190,963 Snackenberg July 11, 1916 1,208,549 Haller Dec.12, 1916 1,233,289 Thomson July 10, 1917 1,366,630 Braman Jan. 25, 19211,862,082 Guffing June 7, 1932 1,866,151 Burnham July 5, 1932

